Disappointment requires adequate planning.
Evolution isn't over. We are the experience that the universe is having.
Brains aren't designed to get results; they go in directions. If you know how the brain works you can set your own directions. If you don't, then someone else will.
There are no failures - only feedback.
The trick is: you have to feel good for no reason.
It's an attitude that has to do with curiosity, with wanting to know about things, wanting to be able to influence things, and wanting to be able to influence them in a way that's worthwhile